Comparison of fast-setting calcium phosphate bone cement and fat autograft in a rabbit model of frontal sinus obliteration.

BACKGROUND: Traditionally, chronic obstruction of the frontal recess is managed by frontal sinus obliteration (FSO). This often requires the harvest of abdominal fat as a filler with all of its associated morbidity. In this study, we investigate the efficacy of calcium phosphate bone cement (Craniofacial Repair System [CRS]) as a material for FSO. METHODS: Eighteen New Zealand white rabbits were divided into three groups and carried out to two time periods. Six rabbits underwent FSO with fat autograft (control group) and 12 rabbits underwent FSO with CRS (study groups 1 and 2, respectively). At 52 weeks, six control and six study rabbits were killed. The remaining six rabbits were killed at 78 weeks. All specimens underwent radiological evaluation with spiral computed tomography (CT) followed by gross inspection. Histological evaluation was then performed to assess bony growth and to evaluate the interface of the sinus wall with the obliterative material. RESULTS: Sinuses obliterated with CRS showed complete obliteration radiographically. This was apparent at 52 weeks and remained static at 78 weeks. Histological analysis indicated persistent obliteration of the sinus cavity from 52 to 78 weeks and signs of osteoinduction. There were no complications observed as a result of the operative procedure or the materials used. CONCLUSION: CRS is an alternative to fat autograft for FSO in this noninfected animal model. Further studies are needed to evaluate its long-term efficacy as well as its behavior in chronically infected sinuses.

Demineralized bone matrix and fat autograft in a rabbit model of frontal sinus obliteration.

OBJECTIVE: In this study, we investigate the efficacy of demineralized bone matrix (DBM) as a material for frontal sinus obliteration in a rabbit model. STUDY DESIGN AND SETTING: Twenty-four New Zealand White rabbits were divided into four groups, and the study was carried out to two time periods. Twelve rabbits underwent frontal sinus obliteration with fat autograft, and 12 rabbits underwent the procedure with DBM. At 12 weeks, six control and six study rabbits were killed. The remaining 12 rabbits were killed at 36 weeks. All specimens underwent radiologic evaluation with spiral CT followed by histologic examination for evidence of bony growth. RESULTS: Sinuses obliterated with DBM showed replacement of the sinus cavity by trabecular bone. Histology demonstrated significant progressive replacement of DBM by cancellous bone from 12 weeks (53.3%) to 36 weeks (78.8%). There were no complications observed as a result of the materials used. CONCLUSION AND SIGNIFICANCE: DBM is a prospective material for frontal sinus obliteration. Long-term studies and human trials will further elucidate the role of this material.